The standard specifies the requirements and test methods, which relate in particular to the manufacture, safety, suitability, purpose and rational use of energy, as well as the classification of gas-fired boilers, which are used for central heating systems. They are equipped with pipes for ventilation and fuel supply and are defined in the standard as boilers. In the standard the term boiler should be understood as the central heating system together with all connecting pipes. The standard should be used in conjunction with the general requirements of the standard EN 15502-2-1. The standard covers gas-fired central heating boilers for types B and C, according to their classification.